Various methods and apparatuses have been taught to cut an enveloped bun-like body by using a continuously fed two-layer material, such as is disclosed in U.S. Pat. Nos. 4,734,024, 4,767,304 and 4,767,305. For example, U.S. Pat. No. 4,734,024 discloses an apparatus for shaping a round body consisting of a dough coating and a filling. It comprises an assembly comprising a plurality of circumferentially disposed members combined to shape a spherical body. Each of the members has at least two sliding surfaces. They are so combined that a sliding surface of one member is slidable on a sliding surface of another member, that by sliding the members an opening is formed or closed in the center of the assembly, and that the opening is confined by walls consisting of the inwardly exposed part of the sliding surface of the members and is of a cross-sectional area. When the opening is completely open it is sufficiently large so as to pass a descending cylindrical body.
While cutting a spherical body by the assembly of slidable members of the prior art is effective, particularly in precluding a member from intruding into the body and thereby breaking the outer layer of the cylindrical body to expose the filling, it has certain disadvantages. Due to configurative and mechanical reasons in both the slidable members and in their assembly, a flower-like pattern is formed on the outer cover when a bar-shaped dough is cut. If a product with an even and smooth outer cover is to be produced, the product must be finished through extra manual work or other means. Also, if a product with a thin outer cover is to be produced, there are cases in which the filling is not completely covered and it is exposed at the center on both the top and bottom of the product, even when a thick dough material is used. Further, these cutting apparatuses may not be ideal for a continuous cutting operation. This is because when a bar-shaped dough material is continuously processed through them for a long time, the dough materials are likely to burn due to the frictional heat generated between slidable members, and they stick to the assembly and interrupt the operation.
Accordingly, one of the objects of this invention is to provide an improved apparatus for cutting a double-layered bar-shaped dough product into double-layered spherical products that eliminates flower-like patterns that are formed on the outer covers of products.
Another object of this invention is to provide an improved apparatus for cutting a double-layered bar-shaped dough product with a very sticky or a highly elastic dough into double-layered spherical products without causing any of the other prior art problems.
Still another object of this invention is to provide an improved apparatus for cutting a double-layered bar-shaped dough product into double-layered spherical products. The apparatus consists of an assembly having at least three circumferentially disposed cutting members, each with at least two sliding surfaces. The members are assembled in sliding contact with each other such that the sliding surfaces of adjacent cutting members are slidable along each other so as to form or close a central opening surrounded by the members. The opening is first opened, and then closed to cut the enveloped body passing through it. One sliding surface of a cutting member forms a convex surface and the other sliding surface forms a concave surface. The convex surface of a cutting member is arranged to slide on the concave surface of an adjacent cutting member and to face the opening when it is opened.
In a preferred embodiment, each of the sliding surfaces facing the opening has a cutout at its outer end.
In another preferred embodiment, the apparatus further comprises a housing for receiving the assembly so constructed that the outer surfaces of the cutting members that form the outer envelope of the assembly slidingly abut the inner surface of the housing.
In another preferred embodiment, the apparatus further comprises a driving means to move the assembly up and down at the same time that the assembly opens and closes.